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Biomedical subjects

J Otten

Publications and source records attributed to J Otten.

At least 73 records · Page 4Linked to original sources
PubMed1991

Ifosfamide-induced Fanconi's syndrome with growth failure in a 2-year-old child.

Fanconi's syndrome with phosphopenic rickets is described in a 2-year-old girl who had been treated for an embryonal sarcoma with multiagent chemotherapy including high-dose ifosfamide. The radiological and biochemical signs of rickets disappeared after treatment with 25-OH vitamin D3 and phosphorus supplements. Monitoring of tubular function in children during and after treatment with ifosfamide is mandatory.

Child, Preschool↗
PubMed1991

High survival rate in advanced-stage B-cell lymphomas and leukemias without CNS involvement with a short intensive polychemotherapy: results from the French Pediatric Oncology Society of a randomized trial of 216 children.

From April 1984 to December 1987, the French Pediatric Oncology Society (SFOP) organized a randomized trial for advanced-stage B-cell lymphoma without CNS involvement to study the possibility of reducing the length of treatment to 4 months. After receiving the same three intensive six-drug induction courses based on high-dose fractionated cyclophosphamide, high-dose methotrexate (HD MTX), and cytarabine in continuous infusion, patients were evaluated for remission. Those who achieved complete remission (CR) were randomized between a long arm (five additional courses with two additional drugs; 16 weeks of treatment) and a short arm (two additional courses; 5 weeks). For patients in partial remission (PR), intensification of treatment was indicated. Two hundred sixteen patients were registered: 15 stage II nasopharyngeal and extensive facial tumors, 167 stage III, and 34 stage IV, 20 of the latter having more than 25% blast cells in bone marrow. The primary sites of involvement were abdomen in 172, head and neck in 30, thorax in two, and other sites in 12. One hundred sixty-seven patients are alive in first CR with a minimum follow-up of 18 months; four are lost to follow-up. Eight patients died from initial treatment failure, 14 died from toxicity or deaths unrelated to tumor or treatment, and 27 relapsed. The event-free survival (EFS), with a median follow-up of 38 months, is 78% (SE 3) for all the patients, 73% (SE 11) for the stage II patients, 80% (SE 3) for the stage III patients, and 68% (SE 8) for the stage IV and acute lymphoblastic leukemia (ALL) patients. One hundred sixty-six patients were randomized: 82 in the short arm and 84 in the long arm. EFS is, respectively, 89% and 87%. Statistical analysis confirms equivalence of both treatment arms with regard to EFS. Moreover, morbidity was lower in the short arm. This study confirms the high survival rate obtained in the previous LMB 0281 study without radiotherapy or debulking surgery and demonstrates the effectiveness of short treatment.

Adolescent↗
PubMed1990

Consolidating the role of *I-MIBG-scintigraphy in childhood neuroblastoma: five years of clinical experience.

In recent years, *I-MIBG (*I-metaiodobenzylguanidine), which is transported and stored in the chromaffin cells, has been shown to allow good visualization of neuroblastomas in children. This paper deals with 30 *I-MIBG-scans performed in 20 children: 16 with neuroblastoma, 3 with retinoblastoma, and 1 with a malignant paraganglioma. A high detection rate was found for both primary and secondary sites of neuroblastoma. *I-MIBG was generally superior to 99mTc-MDP bone scintigraphy in the detection of bone metastases. Our experience illustrates the unique place of *I-MIBG-scintigraphy compared with other imaging techniques: it makes it possible to define the nature of the tumour, particularly in cases with normal catecholamine levels; to establish how extensive the lesions are at the time of diagnosis; and to confirm complete remission. No abnormal *I-MIBG uptake was noted in the 3 cases of retinoblastoma.

3-Iodobenzylguanidine↗
PubMed1990

CSF drug levels for children with acute lymphoblastic leukemia treated by 5 g/m2 methotrexate. A study from the EORTC Children's Leukemia Cooperative Group.

A multicenter EORTC study was conducted in children with acute lymphocytic leukemia to determine whether 5 g/m2 of methotrexate (MTX) (24 h i.v. infusion, four cycles) is an appropriate dosage for obtaining CSF drug concentrations approaching the critical cytotoxic level of 10(-6) M. A total of 193 cycles were analyzed for 58 patients. At the end of the 24 h infusion, the mean MTX serum level was 65.27 +/- 33.11 microM; the mean CSF MTX level was 1.47 +/- 1.1 microM; no significant difference in CSF MTX levels was observed between patients with (n = 20) and those without i.v. Ara-C (n = 38). The mean CSF MTX/serum MTX ratio was 0.029 +/- 0.027. CSF drug concentrations greater than or equal to 10(-6) M were achieved in 81% of the courses. The highest level was 8.4 X 10(-6) M. Only 5% of patients failed to achieve this drug concentration in at least one cycle. No significant correlation was observed between blood and CSF MTX levels. Mean CSF MTX levels were comparable from one cycle to another.

Adolescent↗
PubMed1990

Immunomagnetic purging of bone marrow grafts for autologous transplantation in neuroblastoma.

Bone marrow grafts of 5 patients with stage IV neuroblastoma and one patient with stage IV retinoblastoma were harvested during complete remission and in vitro processed for autologous transplantation. Because of the risk to reinfuse metastatic cells, the grafts were immunomagnetically purged. After preparation of the buffy coat fraction, mononuclear cells (mnc) and progenitor cells (CFU-GM) were enriched by density centrifugation and incubated successively with a cocktail of five tumour reacting monoclonal antibodies and magnetic microparticles. Target cells were removed by a set of samarium cobalt magnets. The purged grafts were stored in liquid nitrogen. After the complete procedure, an average of 16% nucleated cells of the initial harvest could be recovered. This corresponds with a mean number of 0.5 X 10(8) mnc and 2.4 X 10(4) CFU-GM per kg body weight being available for grafting. So far, 5 patients received their purged marrow graft and showed a sustained take.

Bone Marrow Cells↗
PubMed1990

[I-MIBG scintigraphy in the diagnosis of neuroblastoma in children].

Since the early eighties, *I-MIBG (= *I-metaiodobenzylguanidine), which is stored in the neurotransmitter storage granules of chromaffin cells, has been increasingly used for the detection of pheochromocytomas and allied sympathoadrenal pathologies. The aim of this paper is to illustrate, by means of clinical examples, the role of *I-MIBG-scintigraphy in child neuroblastoma and to underline its original place, compared with other imaging techniques, in determining the neuro-ectodermal origin of a tumor as well as in establishing the extension of the lesions at the time of diagnosis and during follow-up.

3-Iodobenzylguanidine↗
PubMed1988

Alkane utilization in Pseudomonas oleovorans. Structure and function of the regulatory locus alkR.

The OCT plasmid-localized alkBAC operon encodes enzymes for alkane hydroxylation and alkanol dehydrogenation. The positively controlled expression of the operon is very efficient in both Pseudomonas putida and Escherichia coli. Two regulatory functions have been ascribed to the regulatory locus alkR: inducer recognition and transcriptional activation of the operon. We have cloned and localized the alkR locus on a 4.9-kilobase pair SalI fragment. The alkR region was analyzed for translation productions in E. coli minicells. Two proteins were identified: a 99- and a 48-kDa peptide. The positions of the cistrons encoding these proteins were established. Both cistrons were shown to be essential for an Alk phenotype. The first cistron (alkS), which encodes the 99-kDa protein, complemented alkR mutations affecting inducer specificity. Furthermore, we found that alkS is responsible for activation of expression of the alkBAC operon since it is required for the induction of the alkB gene product alkane hydroxylase. The second cistron (alkT), which encodes the 48-kDa protein, is required for reconstitution of an Alk phenotype but has no function in regulation of alkBAC expression. Thus, the expression of the alkBAC operon is regulated by a 99-kDa protein, whereas the 48-kDa protein is probably a component of the alkane hydroxylase complex.

Bacterial Proteins↗
PubMed1988

Prognostic factors in 281 children with nonmetastatic rhabdomyosarcoma (RMS) at diagnosis.

Pretreatment characteristics of 281 children with nonmetastatic rhabdomyosarcoma, included in the registry of the International Society of Pediatric Oncology (SIOP) between January 1975 and December 1983, were examined to study the children's prognosis. The multivariate statistical method (Cox regression model) was used for each of two endpoints: survival time and disease-free time. The three most important predictors for survival time were primary site (p less than .001), clinical stage (p = .009), and sex (p = .020). The best results involved paratesticular and orbital primary sites, regardless of the clinical stage; males fared slightly better than females. These same three factors were also significant predictors for disease-free time.

Adolescent↗
PubMed1988

Neuroblastoma today.

Notwithstanding the progress made in radiology, nuclear medicine, immunohematology and genetics for more accurate diagnosis and staging in neuroblastoma and the availability of general new efficacious cytostatic drugs, the prognosis of children over 1 yr with advanced disease has remained poor. New refinements in therapeutics with multiagent regimens, massive chemotherapy followed by autologous bone marrow transplantation treatment, with or without immunomagnetic purging, and/or total body irradiation have improved response rate and disease-free survival in metastatic patients, but their effect on long-term survival needs further evaluation.

3-Iodobenzylguanidine↗
PubMed1986

Leukemia in a trisomy 21 mosaic: specific involvement of the trisomic cells.

Acute monoblastic leukemia was diagnosed in a 32-month-old boy with mild signs of Down's syndrome. Chromosome analysis of cultured skin fibroblasts and peripheral blood lymphocytes disclosed a constitutional mosaicism (46,XY/47,XY,+21). At initial diagnosis of acute leukemia, additional chromosomal changes were found in bone marrow blasts that were consistent with the M5 subtype. The cytogenetic markers of the acute leukemia were restricted to the trisomic subset and disappeared during remission. These findings add further weight to the suggestion that the propensity of Down's syndrome patients to develop leukemia is directly related to their karyotype abnormality and that leukemia might be clonal in origin.

Child, Preschool↗
PubMed1985

Primary chemotherapy in the treatment of rhabdomyosarcoma in children: trial of the International Society of Pediatric Oncology (SIOP) preliminary results.

This therapeutic trial deals with 81 patients with stage III rhabdomyosarcoma (RMS), from different centers of the International Society of Pediatric Oncology. These patients were included between October 1975 and March 1983. The aim of this work is to minimize the sequelae of treatment without jeopardizing the survival rate. After a pretrial course of VAC, two groups of patients are compared: the first treated with systematic extensive surgery or radiotherapy on the initial tumor volume, and the second treated with combined chemotherapy using vincristine, dactinomycin, adriamycin, cyclophosphamide until maximum tumor reduction, followed by radiotherapy or surgery on the residual mass only. Eighty one patients were included in the trail; 15 patients were not randomized due to the failure of the pretrial course of chemotherapy, 3 were excluded after randomization (2 were found not to have RMS, and in one case the protocol was not observed). The preliminary results for the 63 patients show a survival rate of 40% at 3 years. The sequential scheme for patients at 3 years follow-up does not show a superiority in either arm.

Adolescent↗
PubMed1984

Paraaortic lymphadenectomy is not necessary in the treatment of localized paratesticular rhabdomyosarcoma.

Paraaortic lymphadenectomy is routinely recommended to treat paratesticular rhabdomyosarcoma (RMS) because of the high incidence of lymph node involvement. Taking into account the effectiveness of chemotherapy to sterilize micrometastases and aiming to reduce short-term and long-term side effects due to lymph node dissection, the RMS Group of the SIOP decided to avoid lymphadenectomy in Stage I paratesticular RMS defined by (1) complete tumor removal with negative cord section and (2) negative pedal lymphangiography. A series of 19 children (mean age 5 years, 6 months), treated between 1971 and 1981, were analyzed. Eighteen of 19 patients received adjuvant chemotherapy, using vincristine, actinomycin, cyclophosphamide, singly or alternately with vincristine, Adriamycin (doxorubicin) every 3 weeks. Duration was either 18 months (7 cases) or 8 months (11 cases). Fourteen patients are in first remission with a follow-up of more than 3 years (median 5 years); three are disease-free 35, 23, and 20 months since diagnosis; two patients are alive without evolutive disease, 32 and 56 months after an abdominal relapse. Results obtained in this series demonstrate the ineffectiveness of systematic paraaortic lymphadenectomy in Stage I paratesticular RMS and the effectiveness of chemotherapy to eradicate occult micrometastases, which obviously may exist in paraaortic lymph nodes in spite of apparently normal lymphographic findings.

Antineoplastic Combined Chemotherapy Protocols↗